From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=217.70.190.124 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794219941; b=vhfnm6KrVsbkGY9BK3ur3YMFEbNUCkRoxtc9/YmeQJqjD0qbxOhPBS/XuNyfDG9gMtEd meDYP0jSfAJEhe/VnCE157KJeedacFTS+9aA1G0mXxOPwKHYMHZ9rR/5uh3EMXuCun2Rt bHFyJCU+xjRNieScWtxFJTVN3gi+33CbqnNgf1MUlofqHkyI/L4VbRaxn8gN9z0eUr4Z+ uayML0g3XsFOYg8FpH/oEb1oUISrL/ig3LSXdV42vbDVFkg90S9ui3yoYUBsShJgqA7Uj qoYu3KoxLW0xWDtQbjdjpPuLQZSkc9aaNU62+On1om6Hwl5jq76WpxlL+A6aY7+Myng== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794219941; h=DMARC-Filter:DKIM-Signature:Received:Date:From:To:Cc:Subject: Message-ID:References:MIME-Version:Content-Type:Content-Disposition: In-Reply-To:X-Spam-Status:X-Spam-Checker-Version; bh=THZ3FZeaxDmQRkAdlttH8vZVZbyxymyU3JEnnZIjEg8=; b=VZ/1n8DeP7dPU0khkUE/7eMIKFCpI/SZBKMx405KJqxxovlClMnyGZNCzxrL2Qniwe/7 2XE74j+GNpPufi7WVZ6rkkzoTj7YTQNHt3unc9JDiA0rkSfWVoH+fxcbibjZmwwbj50di 8d37rUOfW7fHKIM+14MyGfodDxLCI0v8dbcuLe7xdPdVKaRnTVFsfOi1+6ApoThF5+UJM BzxgExnkGUo6Zf4zaxHnkpJ8gHfKkH7AZowu5MaubillrkUhR2Yv68J8rFHIlO4tHTHDI OIaQJNMxRhIiXj5vsmGionXHdzIRbTbZEzY6aKYVJqOtjC7IRn2YAZrLK6Wh1OPfXpA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none header.from=netfilter.org; spf=pass smtp.mailfrom=netfilter.org; dkim=pass header.d=netfilter.org header.i=@netfilter.org header.a=rsa-sha256 header.s=2025 header.b=vEHNTvxB; arc=none smtp.remote-ip=217.70.190.124 Received: from mail.netfilter.org (mail.netfilter.org [217.70.190.124]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with UTF8SMTPS id E7E4C606A325 for ; Mon, 9 Nov 2026 10:25:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org E7E4C606A325 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=netfilter.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=netfilter.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=netfilter.org header.i=@netfilter.org header.a=rsa-sha256 header.s=2025 header.b=vEHNTvxB DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=netfilter.org; s=2025; t=1794219937; bh=THZ3FZeaxDmQRkAdlttH8vZVZbyxymyU3JEnnZIjEg8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=vEHNTvxBXd9SLws8nYvfh0LLYyk9cVzNGjn2Y9uchNtkaTFM1hC7Js+DD8Htq/RLR xmvNi3h7fuw2ppmNHA5W3e36sONxORyT+k0DG6ifeCwRejjMAOCxceBTEyp85kA+3W cD7fV5BG4a4zLntPw3PxhsGTEfLMVPYW2tcm2yNa1FE4CjvY/QOzIi793T9KWdMbw6 weg70uebY1wzGO3k6xQJydKLIzx1fw37zAUQcAYXWJ9vCMwvKIHZp4955maiIaKQC2 ENDuV0cSH9UXVPkyhmtKYBuzYXpWen/0/MM4qazmlSWHfdTdIDZlQqcxTLEIwbgfsd iOp4HkO4v8dWg== Received: from netfilter.org (mail-agni [217.70.190.124]) by mail.netfilter.org (Postfix) with UTF8SMTPSA id 2F74E60074; Mon, 9 Nov 2026 11:25:37 +0100 (CET) Date: Mon, 9 Nov 2026 11:25:34 +0100 From: Pablo Neira Ayuso To: allfox wy Cc: Florian Westphal , netfilter@vger.kernel.org Subject: Re: [regression] Completely editing packet should be allowed. Message-ID: References: X-Mailing-List: netfilter@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: On Sat, Nov 07, 2026 at 04:04:49PM +0800, allfox wy wrote: > Thank you for explanation. I did a test. It is indeed the protocol > number change in homebrew causing the block. > > However, calling nf_reset_ct(e->skb) would still result in packet > being dropped. I didn't do a precise diagnose to find out where it got > dropped. But replacing nf_reset_ct(e->skb) with "return true" would > result in a working system. > > My deduction: in the system's NAT table there is MASQUERADE in > POSTROUTING. As my understanding, MASQUERADE requires CONNTRACK > information to work. When the outgoing packet going through MANGLE > table and got nf_reset_ct(e->skb), later MASQUERADE in NAT table might > dropped it. > > Is there a function that recalculate the CONNTRACK info rather than > deleting it please? That would entirely conntrack lookup. I think your software should be doing this packet mangling from the prerouting hook *before* the conntrack hook, so you have a chance to create a conntrack object that really represents the flows after your mangling.